Skewback for open hearth furnaces



Oct. 20, 1942. J. F. McLIMANS SKEWBACK ,FOR OPEN HEARTH FURNACES 2 Sheets-Sheet 1 7 Filed Nov. 1, 1941 Firm 6? SKEWBACK FOR OPEN HEARTH FURNACES Filed Nov. 1, 1941 2 Sheets-Sheet 2 JOH/V /2 70/59 /%1//W4A/5,

Patented Oct. 20, 1942 "TED STATES 'IPATENT OFFICE SKEWBACK FOR OPEN HEARTH FURNACES John Fletcher McLimans, Duluth, Minn., assignor to The American Steel and Wire Company of New Jersey, a corporation ofNew Jersey Application November 1, 1941, Serial No. 417,533

9 Claims.

The present invention, relates to: skewbacks peculiarly well. suited for jointly supporting the brickwork of the main arched roof of an open hearth furnace, and the bricks; which constitute the roof for the charging door openings of the furnace.

The invention will be fully apparent from a consideration of the accompanying drawings when read in connection with the following detailed disclosure, and will be defined in accordance with the requirements of the patent stathearth furnace which has the conventional form of front wall l2, back wall l4 and a main arched roof IS. The end bricks l8 of the main arch of the roof, however, are specially shaped to provide notches 26 for engagement with the inwardly projecting rib 22 formed on the skewback, indicated as a whole at 24. The skewback is formed of two separate members 26 and 28,

as illustrated in Figures 4 and 5, the member 28 being herein referred to as the retainer. The

upper extremity of the member 26 is provided a with an outwardly projecting flange 30 through which extends a hanger rod 32 passing through a suitable opening in the flange 30. At its upper end this hanger rod carries nuts 34 which engage an overhead fixed structural support 36. i

The members 26 and 28 of the skewback are detachably secured to one another by bolts 38. The member 26 at its lower end is formed with an outwardly extended projection 40. The outer portion of the retainer 28 is provided with a flange 42 of such cross sectional shape as to provide an inward projection 44. As thus arranged the projections 40 and 44- jointly deflne an undercut or dovetail recess to receive the dovetailed upper extensions ,46, of specially shaped bricks 48 which constitute the roof above the furnace charging door opening 56 formed in the front wall of the furnace.

A water cooling pipe or duct 52 is provided in the lower portion of the member 26 so as to provide for rapidly dissipating the heat in the hottest zone of the skewback structure. The design and construction'of the metallic parts of the skewback unit are such that a considerable surface thereof is exposed to the atmosphere. This advantageously facilitates rapid dissipation of heat to the surrounding atmosphere.

In some cases cooling ribs such as indicated at 54 will be provided to assist in the rapidity of heat dissipation.

The described construction is advantageous since by the provision of the specially shaped hanging brick over the charging door opening there is provided a larger clearance opening, which facilitates the charging of the materials into the open hearth furnace. The shape of the members 26 and 28 is such that the specially shaped skewback channel brick heretofore used is eliminated. This is an economic advantage since such prior art special channel brick is quite expensive and must be entirely removed each time a new roof is put on the furnace.

The herein described brick used for the roof of the furnace door opening having the upwardly extended dovetail projection, in cooperation with the two part metallic skewback, provides means whereby the roof brickwork over the charging I doors can be removed at any time very easily without disturbing the roof proper. This is of material importance in open hearth furnace operation because it permits of easily and inexpensively making repairs to that part of the furout of place.

In prior practice such door brick damage frequently made it necessary to rebuild an entire furnace roof. With the present invention it is only necessary to remove the bolts 38 and separate the retainer 28 a suflicient distance to permit insertion of new brick to replace damaged brick. That brick 48 can also be. inserted into retainer 28 from either end in space marked 40 and by sliding into required space of door. At the same time the specially shaped skewback member 24, because of the inclination of its inner wall and its retaining rib 22, provides a firm support for conventional main roof brick which need only have the outer course formed with one or two notches 26 formed therein.for interlocking engagement with the rib 22. p

The members 26 and 28 of the skewback castings will be made in short lengths so that it willbe relatively simple and inexpensive to replace any part that becomes damaged or worn in operation. This will cut maintenance expense and is more advantageous than theuse of a long continuous casting, as in the prior constructions which usually extended from end to end of the furnace.

While I have described quite precisely the structural design and arrangement of the embodiment of the invention herein illustrated, it is to be understood that various modifications and substitutions of equivalents may be made by those skilled in the art without departure from the invention as defined in the appended claims.

' I claim:

1. A skewback made of separate metallic parts having respective extensions with converging faces jointly forming a dovetail groove adapted to interfit with the correspondingly dovetailed portion of the furnace door opening roof brick.

2. A skewback made of separate metallic parts having respective extensions with converging faces jointly forming a dovetail groove adapted to interfit with the correspondingly dovetailed portion of the furnace door opening roof brick, the said skewback having an inwardly extend ing rib adapted to interfit with a correspondingly formed notch in the furnace roof brick.

3. A skewback made of separate metallic parts having portions jointly defining a dovetail notch and a water cooling duct formed in the lower portion of the skewback in the region of said notch for-coaction with the dovetail portion of the specially shaped furnace door ope IOOf brick.

4. A skew-back comprising a plurality of similar sections arranged end to end so that when any section becomes damaged it may be readily removed without materially disturbing the other sections, said sections of sectional skewback each including separate metallic parts with respective extensions jointly forming an undercut groove adapted to interfit with a correspondingly formed portion of furnace door opening roof brick.

5. An open hearth furnace having an arched roof with charging door openings in the front wall thereof characterized by the novel feature of a skewback member constituting a combined support for said main arched furnace roof and for the bricks constituting the roof of said charging door openings.

6. An. open hearth furnace having an arched brickwork roof and afront wall with charging door openings therein, the tops of said door openings being formed of brick having upward extensions with oppositely projecting overhanging portions and a. skewback having an inner oblique wall portion for engagement with the brickwork of said arched roof and also having an outward projection for coaction with the overhanging portion of the upward projection on the brick over the furnace door, and a retainer detachably secured to the skewback and having an undercut portion for coaction with the outer overhanging portion of the said projection on the furnace door brick.

'7. An open hearth furnace havin an arched brickwork roof and a front wall with charging door openings therein, door roof bricks having upwardly extended dovetail projections formed thereon, a skewback having an oblique inner wall portion against which the weight of the furnace roof brickwork reacts, the lower extremity of said skewback having an inward projection for coaction with the inner part of the dovetail projection on the furnace roof brick, and a retainer detachably secured to the skewback and having an outer flanged portion whose nner face is inclined to fit the inclination of the dovetail projection on said door roof bricks.

8. An open hearth furnace having an arched roof and a front wall with charging door ope ings therein, a metal skewback including an lnne portion with an outwardly and upwardly incline I oblique portion against which the brickwork the furnace roof reacts, an inwardly extended rib formed on the inner face of said oblique wall of the skewback, the outermost bricks of the furnace roof being notched to interfit with said rib, said skewback having an outwardly and downwardly projecting inclined extension at its lower end, a retainer detachably secured to the skewback and having an outer flange whose inher face is inclined upwardly and outwardly, and specially shaped bricks constituting the roof of the furnace door opening having dovetail projections at their upperends for ooaction with said extension on the lower end of the skewback and said flange on the outer portion of said retainer.

9. An open hearth furnace having an arched roof and a front wall with charging door openings therein, specially shaped brick constituting the roof of the furnace door openings, said brick having upwardly extended dovetail projections thereon, a skewback comprising separate members detachably secured to one another-and having portions shaped to interlock with the dovetail projections on said furnace roof brick, one of the members of the skewback having an oblique inner wall against which the bricks of the furnace roof proper react, the said member having an upper outwardly extended flange portion, and an overhead supporting hanger connected to said flange portion.

JOHN FLETCHER MCLIMANS. 

